Apparatus for the telegraphic transmission of written characters.



PATENTED AUGJZl I A. PRANKB. I I HE TELEGRAPHIG TRANSMISSION OF WRITTEN CHARACTERS.

APPARATUS FOR T APPLICATION FILED 0GT17,1902.

3 SHEETS-SHEET 1.

PATENTED AUG. 21, 51906.

A. PRANKE. APPARATUS FOR THE TELEGRAPHI-O TRANSMISSIGN OF WRITTEN CHARACTERS.-

APPLICATION FILED OUT.17; 1902.

3 SHEETBSHEET 2.

LNVENTUR g 44W awn m4 FM No. 829,263 PATENTED AUG. 21, 1906.

' A. FRANKE.

APPARATUS FOR THE TELEGRAPHIU TRANSMISSION OF WRITTEN CHARACTERS;

APPLICATION FILED 00117, 1902.

a sHBBTssHBET 3.

WITNESSES uvvs/vmn 4 2 4, @M fi uM mi/ v i 1 4 AWE/015W) rrn'n STATES PATENT orrron ADOLF FR ANKE, or shoes" LICHTERFELDE, GERMANY.

APPARATUS FOR THE TELEGRAPHIC mus'mssiou or WRITTEN CHARACTERS.

no. eaaeea,

Specification of Letters Patent.

Patented. Aug. 21, 1906.

Application filed October 17, 1902, Serial No. 127.719.

To (Lilac-72,0111, it may concern: 7

Be it known that. I, AnoLF FRANKE, engineer, a subject of the German Emperor, residing at 23 Sternstrasse, Gross Lichterfelde, near Berlin, Germany, have invented certain new and useful Improvements in Appaor elements requisite for producing the char acters into groups and by providing two current impulses of different directiom'the first positive impulse serving to select an element which is exclusively apportioned to a distinct group of letters or characters, while the second negative impulse acts upon an element which does not belong to a group, this element, according to the moment of its operation, serving to select desiredletter from the group.

. A particularly advantageous mode of carrying out this method is obtained by apportioning to each group of letters a distinct element for instance, a condenser for the purpose of reproducing independently all the letters of this group. The firstline'impulse has then the efifect of selecting that particu' lar condenser to the group of which belongs the letter which it is desired totransmit,

while the second impulse causes the selectedcondenser to act so as to produce the desired letter at the proper time.

The application of the telegraphioallytransmitted letter from the synchronously actuated type-whcel to the paper may be effected by a printing device or by photographic means or in any other way. My invention is shown and described in connection with devices for reproducing the characters by means of photography for the purpose of obtaining the greatest possible speed of transmission.

I shall'now proceed'to describe an apparatus constructed according to my invention, in which the number of the necessary relays is reduced to a minimum by the use of con- L densers, which by their discharge produce the printing of the typeupon the paper. A

number of condensers are provided, each of which isadapted to print independently the letters of a definite group. For the purpose of transmitting a particular letter first the condenser in the group of which thedesired letter is contained is charged andthen discharged at-the proper moment. The first and second line impulses effect these two ac-- tions; but in order to produce the currentimpulses exactly at the proper moment there are provided in all the charging and discharg ing circuits two interrupters, which are connected to ether in series, one of them being operated by a part actuated synchronously with the type-wheel.

Figure 1 is a diagram of an apparatus suit able for carrying out the invention. Figs. 2 and 3 are diagrams illustrating two different devices for suddenly illuminating the characters for photographic re roduction. Fig. 4

is a diagrammatic view i lustrating a photographic-printing device which may be employed for printing the characters in carrying out my invention.

n Fig. 1 s s s s represent disks having suitably distributed contact pieces, over which rubthe brushes 1), b b and b that revolve synchronously with the type-wheel. b is connected by lead Z to the contact I of the line-relay r. b is connected by lead Z to contact IV of relay 1", while b and b. are each connected to one pole of the source of current g. In the construction'shownthe letters are divided into nine groups; which circumstance, coupled with an expedient for' the sake of reliability hereinafter referred to, renders it preferable to divide the disks into twelve fields 1 to 12 To each of the first nine contact-pieces c to c of the disk s is connected a group condenser k to it. These condensers are connected with one another through one of their coatings. Their second coatings are connected, as shown lTy leads Z Z l to Z, to contact-pieces insulated from one another of the disks 8 The letters or characters are distributed on the type-wheel correspondin ly to the arrangement and distribution 0 the last-mentioned contact-pieces, so that the grou which is apportioned to the condenser. c

prises only one character. The char g of the group condensers is not effected Exactly from the source of current, 'but through the intermediary which for t s purpose has one of-its coats connected'through lead 1 to the mutually-' connected coats of the group condensers, while its other coat is connected to the armature of the line-relay. v

Fig. 1 shows the condition of the apparatus before sending a character at the m'oment in which the bi'ushes are situated at the commencement of the first field. The

armature of the linerrel" "m is on contact II. The condenser is is cha ged, as will hereina r be described. Let it be assumed, by wa of example, that it is desired to trans- .mit the letter which .is ap ortioned to the is bridged over by the brush at the moment -th$t it rubs over the corres onding third contact-piece of the disk a. consequence of the series connection of two (points of interruption, of which one is close by the part that is ictuated synchronously with the after it has type-wheel, the maintenance of the uniform motion is fa'cilitated, because the line impulse mnst not take place exactly at the moment in which the'brush passes over the contact c. In fact, there is available for that purpose the whole 'eriod of time which is required by the brus after leavin contact 0 toreach the nextcontact c. t this momentnamely, at the moment of contact between I) and c the condenser k 'discharges into the group condenser k After a further rotation through one-twelfth of a revolution the brush 1) establishes connection between the condenser 7c and the con-. denser it"; but in spite of this the latter doesl not receive any discharge of practical importance, because the capacity of the group condensers is reater than the capacity of the charging-con enser, and therefore the latter contains onl a small amount of electricity discharged into the condenser 7c. The condenser is thus charged must now, for the purpose of transmitting the selected letter, be discharged at the moment in which the brush b is just rubbing on. the contactpiece f. 4 This discharge is effected according to the presentinvention by means of a sec-.

( nd current flowing in the opposite direction through the line-relay 1-, which current, according to the example, must arrive at the very moment that the revolving brushes are situated in the sixth field. In passing from of the chargmg-condenser 1:,

,appear to-be practically impossible the letters or characters upon the paper by.

states this field into the next the brush 6 rubsover' a' contact-piece of the disk ?*,-and a=current impulse is thereby produced which travels from the negative pole of the source of current q through 5 contact i,'-lead 1," coil of the relay 27 lead Z, contact 11 to thecondenser k, and thence throughlead I back to the positive pole of the battery. This impulse produces, on the one hand,'the charging of the condenser k for transmittin the next character, and, on the other hand, t e reversal ofthe armature ,of the relay r, so that now the discharge of the condenser k can take place as soon as the arm 11 reaches the contact-piecef, which iii the seventh field of the.

discharging-disk s is apportioned to this condenser. Thus in the case of this last described discharging current-circuit there is employed the principle which was described with reference to the charging of the group condenser and which consists in including m one currentrcircuit two contacts coupled to-'.- gether in series, of which one that prepares the circuit is actuated by the current impulse arriving through the main line, while the-other that closes the circuit is operated by a synchronously-ac ated part of the receiving apparatus. T s arrangement has,

as above stated, the great advantage of not rendering the transmission of a particular character (which in consequence of the use of synchronously-working apparatus depends on the moment at which a current impulse is produced in the receiving apparatus) dependent on .the exact arrival as re ards time of the current which is sent throug the mam line, but of allowing for that event a certain period of time which in the example chosen amounts to about one-twelfth of the period of revolution of the receiving apparatus.

The closing of the circuit for efi'ectin'g the transmission of the character at the proper moment is thus completely insured, because this moment is determined by the receiving apparatus itself.

It is obvious that at the moment of the dis- The apparatus described for the selection of the characters permits a very high speed of transmission The speed obtained with an experimental apparatus constructed as hereinafter described and with simple as distinguished from multiplex working was about two thousand characters per minute. This,

however, is by no means the limit of speed of the apparatus. At such high'spced it would to mark ceases mechanical printing. For this reason a phocoming over the apparatus a, Fig. 1, is used to cause an electric discharge across a sparkgap, located opposite thesign or character to e printed, carried by a rotary type-disk. The arrangement of the mechanism for this urpose is shown diagrammatically in Fi 4.

n this view 3 indicates the type-whee in which the individual characters are arranged in a manner correspondin to-the arrangement of the contacts upon t e disk .9

The characters are made in the form of a stencil, so that the parts-cut out or transpaf ent form the characters. Behind this disk opposite the character then at the printingpoint the spark-gap is formed beween suitable electrodes, said spark-gap being indicated at g. The electrodes are connected to the secondary windings of a transformer 25.

- The primary windings of this transformer are revolution.

included in an electric circuit engaged by the battery (1, which circuit can be closed by the contacts h of the relay 1. Instead of the battery d, obviously some other source of electricity may be employed, for example, a condenser can be used with advantage. The relay r which causes the openin or closing of the contacts h, is located in t e conductors Z, 'Z", and Z at the point indicated at a in Fi 1. A strip p of photographic paper is le over a roller 1' directly opposite the sparkap and on the opposite side of the typeeel from said spark-gap, so that upon the production of a spark the character formed in the type-wheel, which is then exactly before the spark-gap, will be photographed upon the paper. The method of operation of this arrangement will be obvious to those skilled in the art. If the relay 1"? is energized at a certain position of the contact arm by the discharge of a group condenser 7c, k 'k, &c., there results immediately a s ark at the spark-gs g, as will be clear from the drawings, and a p iotographic impression will be made on the aper strip of the character lying opposite t e s ark-gap whose position in'the type-whee corresponds to the position of the corresponding contact upon the disk s It is obvious that the space in front of the type-wheel in which the sensitive strip moves must be inclosed to exclude all light except that coming through the stencil, and the strip after its exposure must be led directly from the dark chamber to developing and fixing baths and then to a suitable washing apps-e ratus. Arrangements of this kind are already old and well known and for this reason have not been illustrated.

After the discharge of the condenser in the described manner the relay 7" must be moved again before the commencement of the next For this purpose there is employed a second coil which is connected at the end of the revolution for a short time with the source of current by means of the disk s", which has a contact only in the twelfth field.

In order to avoid overstraining the linere 7c by the action of the second line impulse can take place in the fields 3 to 11 of the discharging-disk a the discharge of the group condenser k in the fields at to l l, and the dis charge of the roup condenser it" in the fields 5 to 1 1 as will oe seen from the d rawingsthat is to say, the contacts are so arranged that the n grou condensers can only be discharged in t e n 2 and the following fields of the disk 6*. Consequentlythe shortest period of time comprised between the deliveryof the two current impulses required for transmitting a letter is always equal to about one-twelfth of the period of one rcvo lution of the type-wheel or of the brushes. For the same reason a vacant field is provided between the last field in which a dis charge can still take place and the first field in which a charge can again occur in the next revolution. When nine group condensers are used, this renders it necessary to divide the disks or wheels into twelve holds, and it determines the numberand distribution of the discharging contact groups shown on the disk 8 Figs. 2 and 3 illustrate diagrammatically devices for reproducin the characters by means of photography for the purpose of attaining the greatest possible speed of transmission. F or this purpose a sudden illumination of the characters is effected by thecurrent impulses sent from the transmit ter which are utilized to produce eleetricdischarges along a path of sparks at the re (waiving-station. This method has the advantage of providing by the use of a small amount of energya powerful source of light which is Well suited for photographing the characters.

In Fig. 2 l is the line whiclrgees to earth through the Winding of the relay 2. position of rest the spring 3 presses the relayarmature 4 against the rest contact-piece 5,

so that the current-circuit of the battery 6 is interrupted. impulse the reiayermature is pressed against the working contact-piece 7, and thecurrentcircuit is closed through the primary winding 8 of the hiduction-coil, so that in the secondary circuit 9 there is produced a spark which illuminates the type that is situated at that moment in front of the path of sparks. This arrangement makes a great demand on the synchronism of the transmitting, and receiving apparatus, because the current impulse which sets free the sparks must be sent at exactly the moment at which the desired ty e arrives in front of the path of sparks. and t as Qn the arrival of the current In the,

slightest discrepancy i'n'point offtime would necessarily pro uc'e transmission of a wrong character. In order to obviate this and obtain a certain mar in of time for sending the current impulse w ich is necessary to transmit a particular character, the arrangement may be such that the'current impulse of the line shall not setfree the spark, but shall only prepare for its occurrence, while the actual dischargev is effected exactly at the proper time by the type-wheel itself or by means of a part revolving with it. The primary currentcircuit of the induction-coil must, therefore, contain two laces of interruption connected with each ot ier in series, of which. the one is influenced by the armature of the line-relay and the other by the part which revolves syn chronously with the type-wheel. The passage of current in the induction-circuit takes place only when both contacts are closed.-

Therefore the armature of the relay must remain in the position in which it was moved by the line current to transmit the character until the second contact has also been closed and the discharge of s arks has taken place. From this it follows that the relay must be indifferent or neutral and that special means must be provided for opening it or moving it over into the other position. v

Fig. 3 illustrates an arragernent of this kind. The same reference characters indicate the parts similar to those in Fig. 2. 10 indicates a disk which revolves synchronously with the type-wheel and has on its peripheryv suitably-distributed contact-pieces, one for each type on the type-wheel, in such a manner that one of the types is always situated exactly in front of the path of sparks when the brush 13 slides over the corresponding contact-piece. All these contact-pieces are connected electricallv with the metal ring 1]., on which the I brush 12 slides, while the periphery of the disk is traversed by the brush 13. For the purpose of sending a particular characterfor instance, the character which is apportioned to contact-piece 14both the contacts which are in the path c2 the current, the contact at 7, as well as thalv -t 14. must be closed simultaneously; but it is not necessary that 7 should he closed exact ly at the instant in. which the brush 1?, rcachesthc contact-piece l4,and in fact this can take place previously, immediately on the brush 13 leaving the prcccding contact on disk 10. Thus a certain. margin of time is givcn for sending the current impulse so that only a small dcviation in the synchronism docs not afl'cct the transmission of the characters.

'lhc opcration is as follows: The nrrivil'ig linicurrcnt movcs thc armature of the relay up against ihc iontact 7, Where it remains l'cr ihc moment As soon as thc brush 13- coon-s in 'miia t with contact i l of the disk ol' hattcrv i3 is closed. and :i. cm'- i tion, 2cm impulse i gri'oduccd which gives rise to l tioncd sparking. This current impulse serves at t e same-,t me to move the armature of the relay back a ain, for which purpose the impulse is led t rough a second winding 15 of the relay.

The excitation of the primer coil may be done in any of the ways well artas, for example, by means of the working current in the manner described. Also instead of connecting the battery directly with the primary 0011 the. batter may be used to charge a condenser, an the primary coil may be energized by the discharge of the condenser.

Further description modifications are not necessary, are identical as regards their main features, and they are based substantially on one and the same principle.

Having thus articularly described the nature of my said invention and the best means I know of carrying the same into practical flect, I claim 1. In a telegraph-receiver, tion, with means operated by a current impulse in one direction and arranged to select an elementapportioned exclusively to a particular group of characters, of a second element, means for operating said second element by a current impulse in the opposite direction to the first-mentioned current impulse, and means for selecting thereby from the group a character determined by the time of operation of the said second element.

2. In a telegrapli-receiver,,the combination, with means operated by a current impulse in one direction and arranged to select a condenser apportioned exclusively to a particular group of characters, of a relay, means for operating said relay by a current impulse in the opposite direction to the first-mentioned current impulse, and means for selecting therebyfrom the group a character corresponding to the time of operation of the of this and similar relay.

3. In a telegraph-receiver, the combination, with means operated by a current impulse in one direction and arranged to charge a condenser apportioned exclusively to a particular group of characters, of means operated by a second current impulse fand arranged to discharge said condenser at a given moment, and means for selecting vthereby from the group a certainpharacter.

4. In a telegraph-receiver, the combination, with a relay, of condensers apportioned to particular groups of characters, means for charging one of the condensers if the relay is operated in one direction, means for discharging the said coi'idenser if the relay is operated in the opposite direction and means for producing 'thcrcby a character.

In a telegraph-receiver. the combinawith a line-relay, of condensers apporto particular groups of character i own in the because they.

the combina- I rotating contact device for charging one of the condensers if the line-relay is operated in one direction, a rotating contact device for discharging the said condenser if the relay is operated in the opposite direction and means for producing thereby a character.

6. In a telegraph-receiver, the combination', with a line-relay, of condensers apportioned to particular groups of characters, a rotating contact device for charging one of the condensers if the line-relay is operated in one direction, a discharge-relay closing a contact in the discharge-circuit if the line-relay is operated in the opposite direction, a'rotatirg contact device for discharging the con denser if the said contact is closed and means for producing thereby a character.

7. In a telegraph-receiver, the combination, with a line-relay, of condensers apportioned to particular groups of characters,'a main condenser, a rotating contact device for charging one of the first-named condensers,

- by the main condenser if the line-relay is opthe character determined, and

era'ted in the one direction, a discharge-relay closing a contact in the discharge-circuit if the line-relay is operated in the opposite direction, arotating contact device for discharging the condenser if the said contact is closed, means for producing thereby a character, a rotatin contact device for opening the contact m e by the discharge-relay and thereby char ing the main condenser.

8 In a te e aph-recrver, the combination, with a re ay, of condensers apportioned to particular groups of characters, means for charging one of the condensers if the relay is operated in one direction, means for disc arging the said condenser if the relay is operated in the opposite direction,,means for producing a spark and thereby illuminating means for photographicallyreproducing the said character.

9. In a telegraph-receiver, the combination, with a line-relay, of condensers appor.' tioned to particular groups of characters, a rotating contact device for charging one of the c-gwlensers if the line relay is operated in' oneldfvction, a rotating contact device for discharging the said condenser if the relay is operated in the opposite direction, means for producing therebya spark for illuminating the character determined, and means for photographically reproducing the said. char- I acter. u

' 10. In' a telegraph-relay, the combination, with a sunflower contact device, means operated by current impulses in one direction and arranged to close a circuit through one of character selected and arranged in continually increasing numbers between the contacts of the sunflower contact device.

11. In an apparatus for telegraphic trans:

mission ofiwritten characters, t combine-I. t1on, with means for selecting a c aracter, of

means for photographic reproduction, and means for the sudden illumination of said character.

t 12'. In an apparatus for telegraphic transmission of written characters, the} combination, with means for selecting character, of means for photographic reproduction, and an electric sparking-path for the sudden illumination of the characters.

13. In an apparatus for telegraphic transmission of written-characters, the combination, with means for selecting a character, of means for the photographic reproduction of the characters, an electric sparking-path for suddenly illuminating them, two contacts, means forclosing one b an arriving line impulse, a t pe-wheel, an a dpart actuated synchronous y therewith an adapted to close the other contact.

' In testimony whereof I have affixed my signature in presence oi two Witnesses.

,ADOLF FRANKE.

Witnesses WOLDEMAR HAUPT HENRY HASPER. 

